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31.
[目的/意义] 杰青基金实施25年来,资助者年龄呈大龄化趋势发展,深入分析该现象对完成杰青基金的影响,对未来杰青基金管理具有重要意义。[方法/过程] 研究以1994-2018年杰青基金地球科学项目为研究对象,构建科研论文产出效率、创新能力和学术影响力三个评价指标,提出"科技人力资本投入-科研产出"理论模型及假设,采用DID模型克服样本选择性偏误所导致的内生性问题,验证理论假设,实现对杰青基金资助年龄异质性的研究。[结果/结论] 实证结果表明:杰青科学家大龄化趋势日趋严重,存在明显的45岁现象;杰青基金实施20年中,支持"资助年龄越大,资助效应越好"假设的比例较低;三个评价指标维度,资助效应最大且资助年龄在39-42岁之间的年份在杰青基金实施20年中所占比例最大。因此,无论从杰青基金设立宗旨、还是从评估结果来看,都应该避免杰青科学家大龄化趋势,扩大对中低龄优秀青年人才的资助。 相似文献
32.
Participants from the Netherlands (n = 52), China (n = 50), and South Africa (n = 166) either read a self-targeted or a family-targeted fear appeal message about chlamydia. Seven aspects of individual cultural orientation were measured, and six effects of the different messages. Interactions between nationality and target of threat were found on perceived severity, perceived susceptibility, and danger control. Only for perceived susceptibility, a difference in cultural orientation partly explained this interaction. The outcomes add to the doubts about claims in earlier literature about the relevance of receivers’ nationality and cultural orientation for developing a fear appeal message. 相似文献
33.
运用文献资料等研究方法,基于"契机-轨迹"理论,对中美建交40年来体育文化交流情况进行了回顾和梳理,分析了外交政策导向下中美体育文化交流"契机"的形成和"轨迹"的发展,解读中美建交的历史背景和体育文化交流的特征与价值。认为:在"和平与发展""构建开放合作和谐社会""新时代构建新型国际关系"外交政策的影响下,中美体育文化交流具有体育文化财富的共享性、体育竞技的对等性、体育文化交流的公共性特征;中美体育文化交流促进中美建交,促进中美和平发展;改变世界格局,获得话语权;树立国家形象,展示大国责任;深化体育改革,促进社会发展。 相似文献
34.
Digital Module 05: Diagnostic Measurement—The G‐DINA Framework https://ncme.elevate.commpartners.com
In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback. 相似文献
35.
36.
由于月表没有风和流水的侵蚀,月球的反射特性十分稳定,非常适合作为传感器辐射特性监视和定标的参考光源。基于地基对月观测数据,研究人员提出月球辐照度模型。然而现有的模型精度有限,难以满足高精度的应用需求。基于SeaWiFS对月观测数据,对月球反射特性的影响因子以及现有的ROLO和MT2009这两种月球辐照度模型进行分析,为进一步优化月球辐照度模型提供借鉴。 相似文献
37.
Tiziana Lombardo Marie Wörle Vera Hubert Erwin Hildbrand Christina Hinterleitner Ingo Mayer 《文物保护研究》2020,65(2):65-76
ABSTRACTPreviously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO2 was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO2 decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present. 相似文献
38.
借鉴ACSI顾客满意度测评指数模型,结合中国群众性马拉松赛事的特点,运用探索性因子分析法建立中国马拉松赛事参赛者满意度测评指标体系,基于此,构建中国马拉松赛事参赛者满意度测评指数模型。研究发现:中国马拉松赛事参赛者满意度测评指数模型的指标包括参赛者期望、硬服务质量感知、软服务质量感知、感知价值、参赛者满意度、参赛者抱怨、参赛者忠诚度7个因素。就各个自变量对中国马拉松赛事参赛者满意度的影响路径来看,参赛者对服务的预期通过对软服务质量感知、硬服务质量感知间接正向影响中国马拉松赛事参赛者满意度;参赛者的服务质量感知既直接又间接地正向影响参赛者的满意度,参赛者的软服务质量感知通过硬服务质量感知和感知价值间接正向影响参赛者的满意度,参赛者的硬服务质量感知通过感知价值间接正向影响参赛者的满意度。就各个自变量对中国马拉松赛事参赛者满意度的影响程度而言,参赛者的软服务质量感知对其满意度影响最大,其次依次为硬服务质量感知、服务期望和感知价值。 相似文献
39.
《Sport Management Review》2020,23(2):242-255
Competitive sports require a regulating body of referees to enforce the rules for the effective operation of the game. However, the number of referees is generally decreasing, leading to organisational problems at the amateur level. The purpose of this research is to identify the factors that determine the intention to continue voluntary refereeing in the context of football in Germany. Combining several concepts as predictors, including both the antecedents and the experience of volunteering, in this study, the authors extend the understanding about volunteers’ intentions to continue their activity and address the research gap regarding the analyses of specific volunteer groups such as referees. By means of an online questionnaire, the authors surveyed voluntary football referees in Germany (n = 4541). Regression analysis reveals the motive of self-orientation, respect shown by athletes, coaches, and spectators towards referees, compatibility of refereeing with one’s occupational and private life, perceived organisational support, and referees’ satisfaction to predict referees’ positive intention to continue with their activity. Simultaneously, experiences of offences during refereeing negatively influence this intention, and younger referees show higher intentions to continue their activity than do older referees. Because volunteer recruitment and retention are expensive, the findings of this study facilitate the improvement of effective retention strategies for the federations responsible for referees. 相似文献
40.
在新闻智能化传播的环境下,传统媒介的新闻信息资源理念发生变化,智能算法成为新闻信息资源获取和开发的重要手段。智能化传播的新闻信息价值判断,建构了新闻事实信息-社会数据信息-用户需求信息三位一体的新闻信息价值确认系统,体现了智能化新闻信息价值理念的特殊追求。新闻信息生产流程中人工智能系统与新闻传播者形成特殊的生产关系,新闻信息生产理念强调人机协作与共处,由此产生新闻报道视野和新闻产品形态的变化。智能化的新闻发布机制,促进了新闻信息的多渠道推送和分散化传播,也有力推动了传统媒介新闻信息传播理念的智能化转变。 相似文献